Deer with COVID one more worry
Back in August when the U.S. Department of Agriculture revealed that its researchers had found COVID antibodies in about a third of thousands of deer samples they tested from Pennsylvania, New York, Illinois and Michigan — meaning the animals had been exposed to the novel coronavirus causing the pandemic — many of us wondered about the ramifications of the discovery.
Now a Penn State-led study of hundreds of white-tailed deer samples taken between December 2020 and January of this year in Iowa has revealed that a shocking 80% tested positive for the “SARS-CoV-2 virus.”
That shows deer have been infected by COVID and suggests the species may be a reservoir for the disease.
The samples, extracted from lymph nodes in hunter- felled and road-killed deer, had been collected by the Iowa Department of Natural Resources as part of its routine statewide chronic wasting disease surveillance program. The study has not yet been peer reviewed and published in a scientific journal, but Penn State scientists believed their findings so troubling that they wanted to alert deer hunters right away, as hunting seasons are getting underway. The revelation leaves us with many questions:
First, how did deer get COVID? Penn State microbiologists aren’t sure, but after sequencing the genomes of the strains of the virus infecting deer, they do know it came from people because the “lineages” of the viruses circulating in people and deer are the same.
Deer may have been exposed to the disease through wastewater because sewage treatment plants don’t filter out the virus from effluent. Interestingly, although the virus seems to have spread through the deer herds at warp speed, there are no indications the disease killed many or even any animals.
So far, there is no evidence that deer can infect people, but Penn State scientists suggest hunters “wear appropriate personal protective equipment when handling animals and get vaccinated against COVID-19.” In some circles such advice is seen as political, but consider it.
Deer infecting people — the “spillback” possibility — is what scares epidemiologists.
If the virus were to become endemic in deer or other wild animals, they warn, it could evolve over time to become more virulent and then infect people with a new strain capable of evading the current group of vaccines.
“If deer can transmit the virus to humans, it’s a game changer,” Tony Goldberg, a veterinarian at the University of Wisconsin-Madison who studies the evolution of infectious diseases as they jump between animals and people, recently told a major news outlet.
“To have a wildlife species become a reservoir after transmission from humans is very rare and unlucky — as if we needed more bad luck,” he said.
If deer do become a reservoir for the virus – and perhaps they already have – it is one more reason why we will have to learn to live with COVID-19 — the disease may never be eradicated.